Skip to content

univeral capture of stdout and stderr and handling of child process pid for windows, *nix, etc.

License

Notifications You must be signed in to change notification settings

ahoward/systemu

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

61 Commits
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

NAME

  systemu

SYNOPSIS

  universal capture of stdout and stderr and handling of child process pid for
  windows, *nix, etc.

URIS

  http://github.com/ahoward/systemu
  http://rubyforge.org/projects/codeforpeople/

INSTALL

  gem install systemu

HISTORY
  2.0.0
    - versioning issue.  new gem release.

  1.3.1
    - updates for ruby 1.9.1

  1.3.0
    - move to github

  1.2.0

    - fixed handling of background thread management - needed
      Thread.current.abort_on_exception = true

    - fixed reporting of child pid, it was reported as the parent's pid before

SAMPLES


  <========< samples/a.rb >========>

  ~ > cat samples/a.rb

    #
    # systemu can be used on any platform to return status, stdout, and stderr of
    # any command.  unlike other methods like open3/popen4 there is zero danger of
    # full pipes or threading issues hanging your process or subprocess.
    #
      require 'systemu'
    
      date = %q( ruby -e"  t = Time.now; STDOUT.puts t; STDERR.puts t  " )
    
      status, stdout, stderr = systemu date
      p [ status, stdout, stderr ]

  ~ > ruby samples/a.rb

    [#<Process::Status: pid 50931 exit 0>, "2011-12-11 22:07:30 -0700\n", "2011-12-11 22:07:30 -0700\n"]


  <========< samples/b.rb >========>

  ~ > cat samples/b.rb

    #
    # quite a few keys can be passed to the command to alter it's behaviour.  if
    # either stdout or stderr is supplied those objects should respond_to? '<<'
    # and only status will be returned
    #
      require 'systemu'
    
      date = %q( ruby -e"  t = Time.now; STDOUT.puts t; STDERR.puts t  " )
    
      stdout, stderr = '', ''
      status = systemu date, 'stdout' => stdout, 'stderr' => stderr
      p [ status, stdout, stderr ]

  ~ > ruby samples/b.rb

    [#<Process::Status: pid 50936 exit 0>, "2011-12-11 22:07:30 -0700\n", "2011-12-11 22:07:30 -0700\n"]


  <========< samples/c.rb >========>

  ~ > cat samples/c.rb

    #
    # of course stdin can be supplied too.  synonyms for 'stdin' include '0' and
    # 0.  the other stdio streams have similar shortcuts
    #
      require 'systemu'
    
      cat = %q( ruby -e"  ARGF.each{|line| puts line}  " )
    
      status = systemu cat, 0=>'the stdin for cat', 1=>stdout=''
      puts stdout

  ~ > ruby samples/c.rb

    the stdin for cat


  <========< samples/d.rb >========>

  ~ > cat samples/d.rb

    #
    # the cwd can be supplied
    #
      require 'systemu'
      require 'tmpdir'
    
      pwd = %q( ruby -e"  STDERR.puts Dir.pwd  " )
    
      status = systemu pwd, 2=>(stderr=''), :cwd=>Dir.tmpdir
      puts stderr
    

  ~ > ruby samples/d.rb

    /private/var/folders/sp/nwtflj890qnb6z4b53dqxvlw0000gp/T


  <========< samples/e.rb >========>

  ~ > cat samples/e.rb

    #
    # any environment vars specified are merged into the child's environment
    #
      require 'systemu'
    
      env = %q( ruby -r yaml -e"  puts ENV[ 'answer' ] " )
    
      status = systemu env, 1=>stdout='', 'env'=>{ 'answer' => 0b101010 }
      puts stdout

  ~ > ruby samples/e.rb

    42


  <========< samples/f.rb >========>

  ~ > cat samples/f.rb

    #
    # if a block is specified then it is passed the child pid and run in a
    # background thread.  note that this thread will __not__ be blocked during the
    # execution of the command so it may do useful work such as killing the child
    # if execution time passes a certain threshold
    #
      require 'systemu'
    
      looper = %q( ruby -e" loop{ STDERR.puts Time.now.to_i; sleep 1 } " )
    
      status, stdout, stderr =
        systemu looper do |cid|
          sleep 3
          Process.kill 9, cid
        end
    
      p status
      p stderr

  ~ > ruby samples/f.rb

    #<Process::Status: pid 50956 SIGKILL (signal 9)>
    "1323666451\n1323666452\n1323666453\n"


About

univeral capture of stdout and stderr and handling of child process pid for windows, *nix, etc.

Resources

License

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published

Languages